Multiple organ platelet sequestration, hemodynamics, and gas exchange in endotoxin shock and the effects of aspirin-terbutaline treatment.

We studied the effects of two different drugs on multiple organ platelet sequestration, hemodynamics, and respiratory function during endotoxin shock. Twenty-eight sheep (four groups) were anesthetized and ventilated. Group AT-E received aspirin and terbutaline 30 min before and group E-AT 30 min after Escherichia coli endotoxin. Group E also received endotoxin but no drug treatment (shock controls), and group C received neither endotoxin nor drug treatment. There was a marked platelet trapping in the lungs and in the liver immediately after administration of endotoxin in groups E and E-AT, but after 4 hr it was less pronounced in group E-AT than in the endotoxin controls (P < 0.05). In the pretreated animals (group AT-E) there was no increase in platelet sequestration until almost 2 hr after endotoxin both in the lungs and the liver, but at the end of the study (240 min) there was no difference between the pre- and posttreated groups. No significant changes occurred in the kidneys and spleen in any of the groups. In groups E and E-AT the endotoxin infusion resulted in 200% rise in pulmonary artery pressure (PAP) and a sharp decrease in mean arterial pressure (MAP; 25-30%), respiratory compliance (CT; 50%), arterial oxygen tension (PaO2; 70%) as well as in oxygen delivery index (DO2; 30-40%) within 30 min. After 4 hr the PAP had decreased significantly in group E-AT, but remained high in group E (> 100% higher than in group C). Also MAP, PaO2, DO2 and CT improved slightly in group E-AT, while they remained low in group E.(ABSTRACT TRUNCATED AT 250 WORDS)